Model comparison
Grok Code Fast 1 vs Mellum2-12B-A2.5B-Thinking
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Grok Code Fast 1 #180 (Supported); Mellum2-12B-A2.5B-Thinking unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Grok Code Fast 1 and Mellum2-12B-A2.5B-Thinking share 0 comparable benchmark results. 0 of 8 categories are comparable. 12 results are unique to Grok Code Fast 1; 5 to Mellum2-12B-A2.5B-Thinking.
Updated July 23, 2026- Shared results
- 0
- Grok Code Fast 1 only
- 12
- Mellum2-12B-A2.5B-Thinking only
- 5
- Comparable categories
- 0 / 8
Benchmark data for Grok Code Fast 1 and Mellum2-12B-A2.5B-Thinking is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Grok Code Fast 1 has the larger context window at 256K, compared with 128K for Mellum2-12B-A2.5B-Thinking.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Grok Code Fast 1 | Mellum2-12B-A2.5B-Thinking | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Grok Code Fast 1$0.2 input / $1.5 output | Mellum2-12B-A2.5B-ThinkingNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Grok Code Fast 1172 tok/s | Mellum2-12B-A2.5B-ThinkingNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Grok Code Fast 12.81 s | Mellum2-12B-A2.5B-ThinkingNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Grok Code Fast 1256K | Mellum2-12B-A2.5B-Thinking128K | Grok Code Fast 1 lists the larger context window. |
Benchmark Deep Dive
Agentic2 benchmarks
Coding2 benchmarks
Reasoning2 benchmarks
Knowledge9 benchmarks
| Benchmark | Grok Code Fast 1 | Mellum2-12B-A2.5B-Thinking | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 21.6% | — | Not comparable |
| AA-GPQA DiamondSource | 72.7% | — | Not comparable |
| AA-HLESource | 7.5% | — | Not comparable |
| AA-Omniscience IndexSource | -36.0% | — | Not comparable |
| AA-Omniscience AccuracySource | 23.8% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 78.5% | — | Not comparable |
| MMLU-ReduxSource | — | 86.2% | Not comparable |
| GPQASource | — | 57.6% | Not comparable |
| GPQA-DSource | — | 57.6% | Not comparable |
Frequently Asked Questions (3)
Can I compare Grok Code Fast 1 and Mellum2-12B-A2.5B-Thinking on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Grok Code Fast 1 and Mellum2-12B-A2.5B-Thinking today?
Grok Code Fast 1: $0.20 input / $1.50 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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